samples: net: http_get: add support for hl7800 modem

Add overlay and small adjustments for using the hl7800 modem.
Works out of the box with pinnacle_100_dvk and mg100.

Signed-off-by: Ryan Erickson <ryan.erickson@ezurio.com>

samples/net/common/Kconfig

@@ -0,0 +1,12 @@
+#
+# Copyright (c) 2025 Ezurio
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+config NET_SAMPLE_COMMON_WAIT_DNS_SERVER_ADDITION
+	bool "Wait DNS server addition before considering connection to be up"
+	depends on MODEM_HL7800 && !DNS_SERVER_IP_ADDRESSES
+	help
+	  Make sure we get DNS server addresses from the network
+	  before considering the connection to be up.

samples/net/common/net_sample_common.c

@@ -10,7 +10,11 @@ LOG_MODULE_REGISTER(net_samples_common, LOG_LEVEL_DBG);
 #include <zephyr/net/conn_mgr_connectivity.h>
 
 #if defined(CONFIG_NET_CONNECTION_MANAGER)
+#if defined(CONFIG_NET_SAMPLE_COMMON_WAIT_DNS_SERVER_ADDITION)
+#define L4_EVENT_MASK (NET_EVENT_DNS_SERVER_ADD | NET_EVENT_L4_DISCONNECTED)
+#else
 #define L4_EVENT_MASK (NET_EVENT_L4_CONNECTED | NET_EVENT_L4_DISCONNECTED)
+#endif
 
 static struct net_mgmt_event_callback l4_cb;
 static K_SEM_DEFINE(network_connected, 0, 1);
@@ -19,7 +23,11 @@ static void l4_event_handler(struct net_mgmt_event_callback *cb, uint32_t event,
 			     struct net_if *iface)
 {
 	switch (event) {
+#if defined(CONFIG_NET_SAMPLE_COMMON_WAIT_DNS_SERVER_ADDITION)
+	case NET_EVENT_DNS_SERVER_ADD:
+#else
 	case NET_EVENT_L4_CONNECTED:
+#endif
 		LOG_INF("Network connectivity established and IP address assigned");
 		k_sem_give(&network_connected);
 		break;

samples/net/sockets/http_get/Kconfig

@@ -0,0 +1,8 @@
+#
+# Copyright (c) 2025 Ezurio
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+source "samples/net/common/Kconfig"
+source "Kconfig.zephyr"

samples/net/sockets/http_get/overlay-hl7800.conf

@@ -0,0 +1,15 @@
+# The HL7800 driver gets its IP settings from the cell network
+CONFIG_DNS_SERVER_IP_ADDRESSES=n
+CONFIG_NET_CONFIG_SETTINGS=n
+# Wait for the network to be ready
+CONFIG_NET_CONNECTION_MANAGER=y
+CONFIG_NET_SAMPLE_COMMON_WAIT_DNS_SERVER_ADDITION=y
+# NB-IoT has large latency, so increase timeouts. It is ok to use this for Cat-M1 as well.
+CONFIG_NET_SOCKETS_DNS_TIMEOUT=12000
+CONFIG_NET_SOCKETS_CONNECT_TIMEOUT=15000
+
+# CONFIG_MODEM_LOG_LEVEL_DBG=y
+# CONFIG_LOG_PROCESS_THREAD_SLEEP_MS=1
+# CONFIG_LOG_BUFFER_SIZE=20000
+# CONFIG_MODEM_HL7800_SET_APN_NAME_ON_STARTUP=y
+# CONFIG_MODEM_HL7800_APN_NAME="VZWINTERNET"

samples/net/sockets/http_get/overlay-tls.conf

@@ -10,3 +10,7 @@ CONFIG_MBEDTLS_HASH_ALL_ENABLED=y
 CONFIG_MBEDTLS_CMAC=y
 
 CONFIG_NET_SOCKETS_SOCKOPT_TLS=y
+
+# Debugging options
+#CONFIG_MBEDTLS_DEBUG=y
+#CONFIG_MBEDTLS_LOG_LEVEL_DBG=y